Final answer:
The H-Cl bond is the most polar bond listed due to the difference in electronegativity between hydrogen and chlorine, making it a polar covalent bond.
Step-by-step explanation:
The most polar bond among the given options is H-Cl. Polarity in bonds is determined by the difference in electronegativity between the two atoms forming the bond. Hydrogen has an electronegativity value of approximately 2.1, while chlorine has a value of about 3.0. The difference in electronegativity is 0.9, which results in a bond that is definitely polar covalent.
In contrast, bonds like O-O, N-N, and C-C have no difference in electronegativity since they are formed between atoms of the same element, thus they are nonpolar covalent bonds.